Some persons with medical conditions carry medical ID bracelets, often made of metal, with important medical information and contact numbers engraved on them. This can be useful to medical practitioners, if for example the person is found unconscious. In one version of the device the band has a QR code that medical practitioners can scan to be given access to the wearer's medical information held in a central database.
A more recent device is a watch-like bracelet with the body being an electronic monitor for recording personal activity for fitness purposes and also for monitoring sleep.